fdt: add PMU node to fdt

PMU node in fdt stores some important info like irq number.

Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>

arch/src/aarch64/fdt.rs

@@ -51,11 +51,16 @@ const SIZE_CELLS: u32 = 0x2;
 // Look for "The 1st cell..."
 const GIC_FDT_IRQ_TYPE_SPI: u32 = 0;
 const GIC_FDT_IRQ_TYPE_PPI: u32 = 1;
+const GIC_FDT_IRQ_PPI_CPU_SHIFT: u32 = 8;
+const GIC_FDT_IRQ_PPI_CPU_MASK: u32 = 0xff << GIC_FDT_IRQ_PPI_CPU_SHIFT;
 
 // From https://elixir.bootlin.com/linux/v4.9.62/source/include/dt-bindings/interrupt-controller/irq.h#L17
 const IRQ_TYPE_EDGE_RISING: u32 = 1;
 const IRQ_TYPE_LEVEL_HI: u32 = 4;
 
+// PMU PPI interrupt number
+pub const AARCH64_PMU_IRQ: u32 = 7;
+
 // Keys and Buttons
 // System Power Down
 const KEY_POWER: u32 = 116;
@@ -91,6 +96,7 @@ pub fn create_fdt<T: DeviceInfoForFdt + Clone + Debug, S: ::std::hash::BuildHash
     pci_space_info: &[PciSpaceInfo],
     numa_nodes: &NumaNodes,
     virtio_iommu_bdf: Option<u32>,
+    pmu_supported: bool,
 ) -> FdtWriterResult<Vec<u8>> {
     // Allocate stuff necessary for the holding the blob.
     let mut fdt = FdtWriter::new().unwrap();
@@ -114,6 +120,9 @@ pub fn create_fdt<T: DeviceInfoForFdt + Clone + Debug, S: ::std::hash::BuildHash
     create_chosen_node(&mut fdt, cmdline, initrd)?;
     create_gic_node(&mut fdt, gic_device)?;
     create_timer_node(&mut fdt)?;
+    if pmu_supported {
+        create_pmu_node(&mut fdt, vcpu_mpidr.len())?;
+    }
     create_clock_node(&mut fdt)?;
     create_psci_node(&mut fdt)?;
     create_devices_node(&mut fdt, device_info)?;
@@ -540,6 +549,24 @@ fn create_devices_node<T: DeviceInfoForFdt + Clone + Debug, S: ::std::hash::Buil
     Ok(())
 }
 
+fn create_pmu_node(fdt: &mut FdtWriter, cpu_nums: usize) -> FdtWriterResult<()> {
+    let num_cpus = cpu_nums as u64 as u32;
+    let compatible = "arm,armv8-pmuv3";
+    let cpu_mask: u32 =
+        (((1 << num_cpus) - 1) << GIC_FDT_IRQ_PPI_CPU_SHIFT) & GIC_FDT_IRQ_PPI_CPU_MASK;
+    let irq = [
+        GIC_FDT_IRQ_TYPE_PPI,
+        AARCH64_PMU_IRQ,
+        cpu_mask | IRQ_TYPE_LEVEL_HI,
+    ];
+
+    let pmu_node = fdt.begin_node("pmu")?;
+    fdt.property_string("compatible", compatible)?;
+    fdt.property_array_u32("interrupts", &irq)?;
+    fdt.end_node(pmu_node)?;
+    Ok(())
+}
+
 fn create_pci_nodes(
     fdt: &mut FdtWriter,
     pci_device_info: &[PciSpaceInfo],

arch/src/aarch64/mod.rs

@@ -139,6 +139,7 @@ pub fn configure_system<T: DeviceInfoForFdt + Clone + Debug, S: ::std::hash::Bui
     virtio_iommu_bdf: Option<u32>,
     gic_device: &dyn GicDevice,
     numa_nodes: &NumaNodes,
+    pmu_supported: bool,
 ) -> super::Result<()> {
     let fdt_final = fdt::create_fdt(
         guest_mem,
@@ -151,6 +152,7 @@ pub fn configure_system<T: DeviceInfoForFdt + Clone + Debug, S: ::std::hash::Bui
         pci_space_info,
         numa_nodes,
         virtio_iommu_bdf,
+        pmu_supported,
     )
     .map_err(|_| Error::SetupFdt)?;
 

vmm/src/vm.rs

@@ -1172,6 +1172,7 @@ impl Vm {
             virtio_iommu_bdf.map(|bdf| bdf.into()),
             &*gic_device,
             &self.numa_nodes,
+            pmu_supported,
         )
         .map_err(Error::ConfigureSystem)?;
 
@@ -2791,6 +2792,7 @@ mod tests {
             &Vec::new(),
             &BTreeMap::new(),
             None,
+            true,
         )
         .is_ok())
     }